1. Field of the Invention
The present invention relates to an apparatus for generating electric power by a fuel cell reaction by using heat generated in the fuel cell, exhaust heat from factories, or solar energy, and relates to a method therefor.
2. Description of the Related Art
A higher-order utilization system in which electric power is generated by using heat discharged from factories or refuse incinerators is known. A heat energy utilization system is disclosed as a system of this type in Japanese Patent Application Publication No. Hei 1-25972 (hereinafter referred to simply as “Document D1”). The heat energy utilization system has first to third processes. In the first process, organic compounds are dehydrogenated by an action of a dehydrogenation catalyst by using heat from an appropriate heat source such as factory exhaust heat. In the second process, unsaturated organic compounds and hydrogen which are produced by the dehydrogenation reaction in the first process are separated from a non-reacted material. In the third process, the unsaturated organic compounds and the hydrogen which are separated in the second process are reacted by an action of a hydrogenation catalyst, so that energy is generated and the organic compounds which are used as starting materials in the first process are regenerated. In the heat energy utilization system, the first process to the third process are repeated so that energy is obtained by using exhaust heat from the appropriate heat source.
For example, in the above system, electric energy can be obtained by using a method in which the organic compounds and the hydrogen are reacted by the action of the hydrogenation catalyst, for a power generation reaction in the fuel cell.
There are a case in which the secondary obtained heat as described above is expressed as “exhaust heat” which is discharged to the outside and a case in which the secondary obtained heat as described above is expressed as “waste heat” which is not used. In this description, the secondary obtained heat in the above cases is called as “exhaust heat”.
However, in the above system, problems are caused in the separation of the unsaturated organic compounds and the hydrogen from the non-reacted materials in the second process.
That is, a distillation separation or a membrane separation may be used as the above separation. In the distillation separation, it is necessary to cool a distillation material in order to distill, and as a result, heat is discharged to the outside of the system (that is, heat is wastefully lost). Due to this, the distillation separation is undesirable from the point of view of effective heat utilization.
On the other hand, in the membrane separation, it is necessary that a partial pressure of hydrogen at a permeation side be reduced in order to secure the separation efficiency. Due to this, it is necessary to use a vacuum pump or to flow a large amount of purging gas. However, in the case in which the vacuum pump is used, energy consumption by the vacuum pump causes a problem, and energy consumption causes a problem in the case in which the purging gas is flowed.
As described above, in the system disclosed in the Document D1, although the organic compound and the hydrogen are obtained by the exhaust heat, it is necessary to discharge the heat in the separation thereof, or to supply the energy from the outside. Due to this, the efficiency of the system is decreased.